Over the past decade, there has been increased demand for laptop computers, especially in light of their enhanced data processing capabilities. Operating from either external or portable power sources, conventional laptop computers feature a display housing pivotally connected to a body case. Typically, the display housing features a liquid crystal display (LCD) while the body case features a keyboard and a secondary input device, such as a roller ball or a touch pad for example.
In order to access the keyboard and view the LCD, a user places the body case on a surface (e.g., the user's lap or a stationary surface) and opens the laptop computer by pivoting the display housing in an upward angular direction away from the body case. As a result, the user is able to access the keyboard and secondary input device as well as to read the displayed content from the LCD. To close and transport the laptop computer after use, the user pivots the display housing toward the body case and secures the display housing. Such pivoting is accomplished by a hinge attached to a rear surface of the body case.
Due to the growing popularity of personal digital assistants and tablet computers, laptop computers are now being configured to alternatively operate as a tablet computer, with a stylus operating as the input device. This requires the display housing to be inverted, namely the LCD is positioned to face upward and to rest against the body case.
U.S. Pat. No. 5,268,817 illustrates one mechanism in which a display housing is inverted using a secondary hinge positioned to protrude from two opposite side edges of the display housing. Such inversion converts the laptop computer into a tablet computer. However, this conventional display housing possesses a number of disadvantages.
For instance, one disadvantage is that this conventional display housing employs two independent locking mechanisms, namely a pair of locking pins to preclude rotation of the LCD and a lock to attach the display housing to the body casing. Thus, multiple areas of the computer need to be accessed by the user, which makes the locking/unlocking procedure cumbersome. Moreover, independent locking mechanisms may increase overall manufacturing costs and increase the potential likelihood of a structural failure.